Press-roll drive



June 24, 1930.

w. w METCALF ET AL PRES 5 ROLL DRIVE Filed June 17. 1929 2 Sheets-Sheet 1 /-7 J //v ws/v rags Wa/ferh/ Mama/f J epb 5mm? ATTORNEY June 24, 1930.

2 Sheets-Shem 2 /N VENTORS Wa/[er 14 Mercy/f W. W. METCALF ET AL PRESS ROLL DRIVE Filed June 17, 1929 Jose I; Eran n A TTORNE Y Patented June 24, 1930 UNITED STATES PATENT OFFICE WALTER W. METCALF, OF HOOSICK FALLS, AND JOSEPH BROWN, OF MIDDLE FALLS,

N YORK PRESS-ROLL DRIVE Application filed June 17,

ing the paper through what are termed press rolls. The bottom roll is covered with rubber, the upper one is of wood, metal or stone and passing between them with the paper is a belt of felt. These rolls are generally long and of rather large diameter to give a large pressure for a considerable area. The lower roll is power driven, while the upper one has some weight or force applied to it, so that there will be suflicient pressure on the zone of contact. The upper roll is frictionally driven through the felt.

After being in use the rolls develop irregularities and it becomes necessary to turn or trim them down. lVhen the rolls are turned down and replaced in the machine the peripheral speed remains practically constant and equal, but due to reduction or variation in size the angular speed of the rolls and the ratio of their angular speeds has changed.

Due to the pressure of the rolls, there is more or less tension on the 'felt as it is pulled through the press rolls. This has a tendency to unequally stress and distort the meshes of the felt. When the meshes are distorted, or pulled out of shape they are partially closed, and the water from the paper does not pass through-the felt as rapidly as it should. This being the case, the pressure of the rolls must be increased which causes the felt to become thin, to wear rapidly, and the rolls to develop irregularities. These irregularities in the rolls cause the water in the paper to be squeezed out unevenly. Much of the wearing of the felt and the rolls would be obviated or lessened to a great extent if both upper and lower press rolls were power driven. The nip of the rolls would be even and the pressure could be adjusted more accurately. Our invention, more particularly described below, discloses a device for driving both upper and lower press rolls at the same angular speed.

Our invention therefore includes the novel 1929. Serial No. 371,423.

elements and the combinations and arrangements of elements described below and illustrated in the accompanying drawings in which Fig. 1 is a vertical section of the differential gear taken substantially on line 1-1, as shown in Fig. 2, with part of the housing and some'of the gears and pinions removed;

Fig. 2 is a front view of the differential gearing with the front housing removed;

Fig. 3 is a general partial elevation of the power driven press rolls showing the arrangement of gears to drive both rolls;

Fig. 4 is a fragmentary axial section of the differential gearing;

Fig. 5 is a fragmentary axial section showing the connection of the shafts to the press rolls; and

Fig. 6 is a fragmentary view of the gear connections of the press rolls showing how the gear teeth may be shortened.

Referring to the drawings, power is transmitted to the bevel gear, 1, which is riveted or otherwise secured to the differential housing, 2., Journaled within the housing on stub shafts, 3, are six planetary pinions, meshed in pairs. One pinion, 4, of each pair meshes with the rear sun wheel, 6, while the other pinion, 5, is geared to the front sun wheel, 7

The rear sun wheel, 6, is keyed to the solid inner shaft, 8, and the front sun wheel, 7, is keyed to the hollow, cylindrical, outer shaft, 9. This outer shaft, 9, is keyed to spur wheel, 11, which drives spur wheel, 13, keyed to the shaft, 15, of upper roll, 17.

The inner solid shaft, 8, is directly connected to the lower press roll, 10.

The spur wheels, 1'1 and 13, have teethJc, shown in a fragmentary way. in Fig. 6. From this figure, it will be apparent that the tips of teeth, 70, are filed or chipped off to permit the adjustment of the cylinders and 5. However, if in the turning down of the cylinders the diameters are not the same the pinions in the differential will revolve so that one shaft will revolve faster than the other, the smaller cylinder turning faster until the work done by both shafts is equal, which means that the peripheral speeds are the same.

This is the well known principle of the action of a differential gear.

While we have described our invention in its preferred embodiment it is to be understood that the words which we have used are words of description rather than of limitation and that the drawings are merely illustrative. Hence changes, within the purview of the appended claims, may be made without departing from the true scope and spirit of our invention.

What we claim is- 1. In a paper making machine, the combi-- nation with upper and lower press rolls of a differential gear, and means for driving both rolls.

2. In a paper making machine, the combination with an upper and lower press roll, of means for positively driving both rolls at the same peripheral speed,

3. In a paper making machine, the combination with a pair of press rolls, of means for positively driving both rolls at the same peripheral speed irrespective of their relative diameters.

4. In a paper making machine, the combination with a pair of rolls between the nip of which the paper runs, of means for positively driving both rolls at the same peripheral speed irrespective of their relative diameters.

5. In a paper making machine, a power driven differential gear keyed to two shafts, each shaft connected to one of a pair of adjecent press rolls between the nips of which the paper moves.

6. In a paper making machine, the combination with an upper and lower press roll, each roll having a surface material different than the other, of means for positively driving both rolls at the same peripheral speed irrespective of their diameters, or surfacing.

7. In a paper making machine, a driven differential gear keyed to two independent shafts, one wholly contained in the other and each shaft connected with one of a pair of adjacent press rolls. 8. In a paper making machine, a power driven differential gear keyed to two shafts, one wholly contained in the other, the inner shaft directly connected to one of a pair of adjacent press rolls and the other shaft c011- nected to the other press roll by gears.

9. In a paper making machine, a power driven differential gear keyed to two shafts, one contained within the other but said shafts may be rotated at different speeds, 

